University of Colorado at Boulder researchers will test the effects of low gravity on two biomedical experiments aboard the upcoming flight of NASA聮s space shuttle Atlantis, now slated for liftoff Sept. 8 from Cape Kennedy, Fla. to the International Space Station.
One experiment will study the effects of spaceflight on the neural development in various larval stages of the common fruit fly, which should provide scientists with new insight on how gravity affects nerve growth and development. The experiment, which is being flown for Yale University and NASA Ames Research Center scientists by the CU-headquartered BioServe Space Technologies Center, also should provide a better understanding of the nervous system and its connections to muscle fibers.
Co-sponsored by the National Institutes of Health, the experiment will be flown in a device developed by BioServe known as the Commercial Generic Bioprocessing Apparatus, or CGBA, said BioServe Director Louis Stodieck. Evolving versions of the suitcase-sized CGBA have supported dozens of agricultural, biomedical and biotechnology experiments in thousands of customized test tubes on NASA shuttle missions in the past decade.
The seven Atlantis crew members will spend a week docked to the space station, unloading more than a ton of equipment and supplies from the shuttle and from a docked Russian cargo craft. BioServe聮s experiments will return to Earth on Atlantis on Sept. 19.
In the fruit fly experiment, larvae in differing stages of development will be placed inside petri dishes in the CGBA modules. Fluorescent genes known as "reporter genes" will be injected into the larvae prior to flight, making their nervous systems glow, said Stodieck, also an associate research professor in the aerospace engineering department. "When these larvae are put under a microscope, their entire neural systems light up."
The CGBA will keep the fly larvae at 53 degrees Fahrenheit during the beginning of the 11-day flight, then warm them to 65 degrees to speed up neural development. After the neural systems have developed to desired stages, the larvae will be automatically re-cooled by the automated hardware. "This provides a full sequence of their neural development, allowing researchers to see nerve cell-muscle processes interactions," said Stodieck.
BioServe is a NASA Commercial Space Center established in 1987 at CU-Boulder in collaboration with Kansas State University to develop new or improved products through space life-science research in partnership with industry, academia and government. Bioserve payloads have been launched on 17 NASA space shuttles since 1991, have twice ridden on Russia聮s Mir Space Station, and are expected to have a permanent presence on the International Space Station beginning in 2001.
BioServe also will be using the Atlantis flight for a follow-up experiment from a previous microgravity experiment to demonstrate interactions in the gene expression in kidney cells in low gravity. The kidney-cell experiment is a collaboration between BioServe and Tulane University. Both the kidney cell experiment and the fruit fly experiment are sponsored through the Fundamental Biology Program at NASA-Ames.
Cells grown in the suspension of space form three-dimensional tissues similar to their counterparts in intact, living organs, said David Klaus, BioServe聮s associate director for research. "Kidney cells on Earth tend to fall to the bottom of culture dishes and form a flat surface," said Klaus, also aerospace research faculty member. "But in space they are suspended throughout the culture, allowing them to aggregate and communicate more naturally with each other."
Tulane researchers want to better understand gene expression in space-cultured kidney cells and develop new applications related to tissue engineering, said Klaus. They particularly are interested in trying to increase the amount of Vitamin D naturally produced by kidney cells, which helps maintain calcium and phosphate levels in human blood.
A sophisticated container known as an Isothermal Containment Module developed by BioServe will automatically heat the kidney cell samples to the normal human body temperature of 98.6 degrees F. Samples will be drawn from the cell cultures and a preservative automatically added at a predetermined time in orbit. After the flight, the samples will be analyzed for changes in gene expression that occurred during the mission.
Research on the International Space Station will begin next spring after the laboratory module and a permanent crew are in place. The station will provide low-gravity conditions for months on end for experiments designed by students, researchers and faculty, said Stodieck.
A shuttle experiment conducted in collaboration with Bristol-Myers Squibb Pharmaceutical Research Institute in 1998, for example -- which showed the production of the antibiotic actinomycin D was significantly higher in space -- will likely fly next April on the space station, Klaus said.